The Cubs made an addition to the bullpen prior to the opener of the three-game series with the Nationals on Friday. The Cubs inked veteran southpawJorge De La Rosa to a contract. LHP Randy Rosario was sent down to Iowa in an exchange of lefty relievers.

To make room on the 40-man roster for De La Rosa, RHP Yu Darvish was transferred to the 60-day disabled list.

LHP Jorge De La Rosa, 37, was in the Diamondbacks pen this season. De La Rosa was 0-2 with a 4.63 ERA and 1.60 WHIP. In 35 innings, De La Rosa allowed 19 runs, 18 earned, on 37 hits with 19 walks and 27 strikeouts.

De La Rosa signed a one-year, $2.25 million contract with Arizona in the off-season. De La Rosa was designated for assignment on July 31 and released by the D-Backs on Aug. 4. De La Rosa will only cost the Cubs a prorated portion of the league minimum.